<?php

declare(strict_types=1);

namespace GuzzleHttp\Psr7;

use Psr\Http\Message\StreamInterface;

/**
 * Stream that when read returns bytes for a streaming multipart or
 * multipart/form-data stream.
 */
final class MultipartStream implements StreamInterface
{
    use StreamDecoratorTrait;

    /** @var string */
    private $boundary;

    /** @var StreamInterface */
    private $stream;

    /**
     * @param array  $elements Array of associative arrays, each containing a
     *                         required "name" key mapping to the form field,
     *                         name, a required "contents" key mapping to a
     *                         StreamInterface/resource/string, an optional
     *                         "headers" associative array of custom headers,
     *                         and an optional "filename" key mapping to a
     *                         string to send as the filename in the part.
     * @param string $boundary You can optionally provide a specific boundary
     *
     * @throws \InvalidArgumentException
     */
    public function __construct(array $elements = [], string $boundary = null)
    {
        $this->boundary = $boundary ?: bin2hex(random_bytes(20));
        $this->stream = $this->createStream($elements);
    }

    public function getBoundary(): string
    {
        return $this->boundary;
    }

    public function isWritable(): bool
    {
        return false;
    }

    /**
     * Get the headers needed before transferring the content of a POST file
     *
     * @param string[] $headers
     */
    private function getHeaders(array $headers): string
    {
        $str = '';
        foreach ($headers as $key => $value) {
            $str .= "{$key}: {$value}\r\n";
        }

        return "--{$this->boundary}\r\n".trim($str)."\r\n\r\n";
    }

    /**
     * Create the aggregate stream that will be used to upload the POST data
     */
    protected function createStream(array $elements = []): StreamInterface
    {
        $stream = new AppendStream();

        foreach ($elements as $element) {
            if (!is_array($element)) {
                throw new \UnexpectedValueException('An array is expected');
            }
            $this->addElement($stream, $element);
        }

        // Add the trailing boundary with CRLF
        $stream->addStream(Utils::streamFor("--{$this->boundary}--\r\n"));

        return $stream;
    }

    private function addElement(AppendStream $stream, array $element): void
    {
        foreach (['contents', 'name'] as $key) {
            if (!array_key_exists($key, $element)) {
                throw new \InvalidArgumentException("A '{$key}' key is required");
            }
        }

        $element['contents'] = Utils::streamFor($element['contents']);

        if (empty($element['filename'])) {
            $uri = $element['contents']->getMetadata('uri');
            if ($uri && \is_string($uri) && \substr($uri, 0, 6) !== 'php://' && \substr($uri, 0, 7) !== 'data://') {
                $element['filename'] = $uri;
            }
        }

        [$body, $headers] = $this->createElement(
            $element['name'],
            $element['contents'],
            $element['filename'] ?? null,
            $element['headers'] ?? []
        );

        $stream->addStream(Utils::streamFor($this->getHeaders($headers)));
        $stream->addStream($body);
        $stream->addStream(Utils::streamFor("\r\n"));
    }

    /**
     * @param string[] $headers
     *
     * @return array{0: StreamInterface, 1: string[]}
     */
    private function createElement(string $name, StreamInterface $stream, ?string $filename, array $headers): array
    {
        // Set a default content-disposition header if one was no provided
        $disposition = self::getHeader($headers, 'content-disposition');
        if (!$disposition) {
            $headers['Content-Disposition'] = ($filename === '0' || $filename)
                ? sprintf(
                    'form-data; name="%s"; filename="%s"',
                    $name,
                    basename($filename)
                )
                : "form-data; name=\"{$name}\"";
        }

        // Set a default content-length header if one was no provided
        $length = self::getHeader($headers, 'content-length');
        if (!$length) {
            if ($length = $stream->getSize()) {
                $headers['Content-Length'] = (string) $length;
            }
        }

        // Set a default Content-Type if one was not supplied
        $type = self::getHeader($headers, 'content-type');
        if (!$type && ($filename === '0' || $filename)) {
            $headers['Content-Type'] = MimeType::fromFilename($filename) ?? 'application/octet-stream';
        }

        return [$stream, $headers];
    }

    /**
     * @param string[] $headers
     */
    private static function getHeader(array $headers, string $key): ?string
    {
        $lowercaseHeader = strtolower($key);
        foreach ($headers as $k => $v) {
            if (strtolower((string) $k) === $lowercaseHeader) {
                return $v;
            }
        }

        return null;
    }
}

• [D] Exception
• [F] AppendStream.php
  Delete
• [F] BufferStream.php
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• [F] CachingStream.php
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• [F] DroppingStream.php
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• [F] FnStream.php
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• [F] Header.php
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• [F] HttpFactory.php
  Delete
• [F] InflateStream.php
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• [F] LazyOpenStream.php
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• [F] LimitStream.php
  Delete
• [F] Message.php
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• [F] MessageTrait.php
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• [F] MimeType.php
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• [F] MultipartStream.php
  Delete
• [F] NoSeekStream.php
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• [F] PumpStream.php
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• [F] Query.php
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• [F] Request.php
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• [F] Response.php
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• [F] Rfc7230.php
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• [F] ServerRequest.php
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• [F] Stream.php
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• [F] StreamDecoratorTrait.php
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• [F] StreamWrapper.php
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• [F] UploadedFile.php
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• [F] Uri.php
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• [F] UriComparator.php
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• [F] UriNormalizer.php
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• [F] UriResolver.php
  Delete
• [F] Utils.php
  Delete

About Section

About NFC Pay: Our Story and Mission

NFC Pay was founded with a vision to transform the way people handle transactions. Our journey is defined by a commitment to innovation, security, and convenience. We strive to deliver seamless, user-friendly payment solutions that make everyday transactions effortless and secure. Our mission is to empower you to pay with ease and confidence, anytime, anywhere.

• Simplifying Payments, One Tap at a Time.
• Reinventing Your Wallet for Modern Convenience.
• Smart Payments for a Effortless Lifestyle.
• Experience the Ease of Tap and Pay.
• Innovative Solutions for Your Daily Transactions.

FAQ Section

Frequently Asked Questions About NFC Pay

Here are answers to some common questions about NFC Pay. We aim to provide clear and concise information to help you understand how our platform works and how it can benefit you. If you have any further inquiries, please don’t hesitate to contact our support team.

How do I register for NFC Pay?

Download the app and sign up using your email or phone number, then complete the verification process.

Is my payment information secure?

Yes, we use advanced encryption and security protocols to protect your payment details.

Can I add multiple cards to my NFC Pay wallet?

Absolutely, you can link multiple debit or credit cards to your wallet.

How do I transfer money to another user?

Go to the transfer section, select the recipient, enter the amount, and authorize the transfer.

What should I do if I forget my PIN?

Use the “Forgot PIN” feature in the app to reset it following the provided instructions.

How can I activate my merchant account?

Sign up for a merchant account through the app and follow the setup instructions to start accepting payments.

Can I track my payment status?

Yes, you can view and track your payment status in the account dashboard